In waiting for my first TL piece, and my current piece needs some colour as it has lightened up and it's not blending as well as I need it. The colour ordered from TL was a #3. I was in the drug store and looked at product but it's hard to figure out what matches my own hair, considering its on my head and there were tons of samples

For those of you with a TL #3 colour, what off the shelf product and colour would you recommend? Some brands use numbers, some names etc.

thanks